Transcript for Pilots, Flight Attendants Revolt Against New TSA Policy

the airline industry, the revolt by some flight attendants and pilots allowing passengers to carry small knives. Here's abc's david kerley on the red-hot debate. Reporter: The roar of protests over tsa's plan to allow small knives on planes grew louder today. Massachusetts congressman ed markey is now joining the chorus with a warning. If the tsa does not reverse their decision, I'm going to introduce legislation to reverse the decision. Reporter: It's these small pocket knives, with small blades, that the tsa planning to allow back on planes. The ceo of the largest airline, delta airlines, joined the cause last night with a letter to the head of the tsa quote, we share the legitimate concerns. We're not going to stand for that. The tsa was created because there were blades in the cabin. Reporter: The air marshal unions has joined the unions has joined the opposition, which has gained steam with an online petition. He said that allowing small knives will allow his officers to concentrate on explosives. Especially liquid explosives. But those who work in aircraft cabins say it's a dangerous move. It makes no sense for us to say that we can only search for liquid explosives or knives. We should be able to search for both. criticism, the tsa tells me again tonight, it's going ahead with it plans. Starting april 25th you can carry one of these small knives on to plane. David kerley in washington,

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